The present invention relates to a wafer for the fabrication of III-nitride power devices and III-nitride power devices formed using a wafer according to the present invention.
III-nitride, because of its high bandgap, is suitable for high voltage power applications. According to a known design, a III-nitride power device may be fabricated by forming a III-nitride heterojunction over a silicon substrate. However, due to leakage through the substrate, the breakdown capability of such devices is diminished.
An objective of the present invention is to provide a wafer for the fabrication of III-nitride devices, and particularly, high voltage (above 600 Volts) III-nitride power semiconductor devices.
A semiconductor wafer according to the present invention includes a support substrate having a first silicon body, a second silicon body and an insulation body interposed between the first silicon body and the second silicon body, and a III-nitride body formed over the second silicon body.
The III-nitride body preferably includes a III-nitride heterojunction comprised of a first III-nitride layer of one band gap and a second III-nitride layer of another band gap formed over the first III-nitride layer. The III-nitride body may further include a III-nitride buffer layer interposed between the III-nitride heterojunction and the second silicon body.
According to one aspect of the present invention, the second silicon body may be comprised of <111> silicon. In one embodiment, the first silicon body may be <111> silicon, and in another embodiment the first silicon body may be <100> silicon. In both embodiments, the insulation body may be comprised of silicon dioxide.
According to another aspect of the present invention, the III-nitride body may be used for the fabrication of a power semiconductor device.
Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings.